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Post #51 has the test data. The #27 Hodgdon manual uses the Sierra 180 SPBT. Note in the test results the near SEE. I used a Federal 210 primer in my test. I am going to retest with WLR primer which is the primer Hodgdon used.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

Mr. Gibson, as I said earlier, here is the published load data for the 6PPC and 6BR.

For the PPC, the most common powder used by far is VV N133. The VV 2-01 manual shows a maximum charge using a Euber 68 grain bullet and N133, is 28.1 grains. Most shooters START higher than that. A maximum to some is 30.8 grains. I have heard of velocities that defy logic, but they do it. I personally wouldn't get close the that, but many do with regularity.

For the 6BR and Varget powder, the Hodgdon 27 manual for a 100 grain bullet, is 28.0 grains. Most use a 105-107 grain bullet, and a 30.0 grain load is common with some going higher than that.

I used to shoot a 308 quite a bit, but that was a long time ago and can't remember the load. It was over published data.

Let me say again, this is done with custom actions and match chambers. And the sizing dies are matched to the chambers, so the brass doesn't suffer. The run of the mill, off the shelf gun, can't handle it.

All the acronyms in the world used to explain why this can't be done, doesn't work.

All that load data is fine but what, pray tell, is the accepted "normal" maximum pressure for either cartridge? You don't know because there isn't one as neither cartridge is a standardized SAAMI or CIP cartridge. Exceeding an establish measured maximum pressure is the thrust of this thread. Because you use higher loads than published for those two non standardized cartridges does not mean you are using excessive pressures in either cartridge. You can not tell us what is an established MAP for published loads of either cartridge nor can you tell us what the pressures of your own loads are or that.....can you?

What I'm saying here is the highest established MAP (SAAMI or CIP) for any cartridge with a 30-06 head sized cartridge is 65,000 psi in modern actions. That includes the 270 Win, .308W, 243 Win, 260 Rem, 25-06, 22-250, etc. It also includes the 6 BR. The 6 PPC using a SR primer has sufficient case support around the primer to support 62,000psi also as does the smaller 5.56 cartridge. Thus any average psi over that 62,000 psi measured under standard test conditions should be considered "excessive" pressure.

Now, can you show us that either of the loads you use in the 6 PPC or the 6 BR have a measured psi in excess of 62,000 psi? If not, then regardless that your loads exceed published data, if they do not exceed 60 to 62,000 psi then they do not have "excessive" pressure for either the cartridges or for the modern actions they are used in.

The topic of this thread, once again, is a 30-06 load less than published max loads which exceeded 62,000 psi by a measured considerable margin and which demonstrated excessive pressure by expanding primer pockets.

Last edited by Larry Gibson; 10-10-2017 at 08:40 PM.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

I am done arguing. I understand what the points are you are trying to make. My point all along is simply that published data, isn't necessarily gospel. Just because it is written down, doesn't make it right. Let your gun tell you what maximum is, it varies.

"My point all along is simply that published data, isn't necessarily gospel. Just because it is written down, doesn't make it right. Let your gun tell you what maximum is, it varies."

That is the point I made early on. This whole thread wasn't about anything else but load data from any source is not concrete, positive, non negotiable, holy writ, 100 percent accurate, undeniable, factual, spot on, unquestionable, non variable and whole list of other things it isn't.
I always consult more that one source of data both old and new to newest I can find. Then I make a determination as to where I start and stop.
C-A-U-T-I-O-N is the word.
But Mr Gibson being an owner of a personal ballistic lab and having a mind for data is now supplying us with more data. Which, with him being an honest man will readily tell you his data is just more data that is not concrete, positive, non negotiable, holy writ, 100 percent accurate, undeniable, factual, spot on, unquestionable, non variable, and a whole list of other things it isn't.
Let him run the same test two years from now with entirely different "lots" of the same components and see if it is.
I don't think for one minute he will do the thing on our legs and try to tell us it's raining. Unless my opinion of him is badly flawed.
Don't make more out of this thread than what it was. Just a warning and nothing else.

Last edited by 44MAG#1; 10-10-2017 at 09:01 AM.

We Know Mass Cannot Be Weighed But It Has Newtonian Weight And That Is Derived From Kilograms And Kilograms Can Be Converted to Pounds. But, Still Mass Cannot Be Weighed. But How is the kilograms obtained? Can Kilograms Be Weighed? Evidentally Yes It Can. But, Still Mass Cannot Be Weighed So Kilograms Must Not Exist. Funny Isn't It.
One good thing out of this the next time I'm at the doctors and they want to weigh me I'll tell them mass cannot be weighed.

BR Shooter, your gun is an idiot and prone to not telling anybody anything until the news is really depressing.

I suggest to the rest that experienced shooter/loaders realize that every gun and load is a sea of variables that skew off the course from published data. Brass is a variable, primers/powder/bullets/bore condition etc. etc ad nauseum are all their own merry carnival. A prudent and disciplined mind will resist the notion that it is special, blessed, immune to such mundane things as engineering principals, standard deviations, MAP and so forth. You mommy gave you but one face, take care of it.

Larry, I appreciate your effort on this, thank you for the investigation and report.

"What I'm saying here is the highest established MAP (SAAMI or CIP) for any cartridge with a 30-06 head sized cartridge is 62,000 psi in modern actions."
Not quite correct, ie 6mm Remington SAAMI MAP 65,000 PSI, 25-06 63,000 those both are 06 head size. The whole point is loading manuals are just guidelines used to establish a maximum load in your rifle with your components. A seasoned hand loader learns to watch for signs of excess pressure and adjust accordingly, signs like sticky extraction, very sharp transition from case body to pressure ring at web which is visible even on a case fired in min spec chamber(your case) and more so on a production chamber, brass extruded into bolt face and especially LOOSE primer pockets after only a couple firings. Reduce down 5% and you will be safe! Fire these loads for velocity and accurracy, if they don't meet your needs change components until it does. Science is important in handloading but you've just got to have the "street smarts" to keep your eyes and fingers intact. The data Hodgdon published could very well be safe(at or below SAAMI MAP) in their barrel and EXACT components they used. Correct me if I'm wrong, but isn't the criteria for canister grade powders +- 5% of average burn speed per lot to lot variation?

"MAP stands for maximum average pressure. What is the max peak pressure for the cartridges?"

Who cares? That not really the meat of this topic. This can be discussed, cussed, argued, debated, whined about, even cried about but the meat of this thread is no load date whether it is SAMMI set, wildcatter set, or crystal ball set or seasoned home reloader set is not 100 percent reliable.
Real meat of this thread is: USE CAUTION WHEN WORKING UP LOADS IN ANY FIREARM using any source of written, vocal, or assumed data from any source including people on here or from the labs.

We Know Mass Cannot Be Weighed But It Has Newtonian Weight And That Is Derived From Kilograms And Kilograms Can Be Converted to Pounds. But, Still Mass Cannot Be Weighed. But How is the kilograms obtained? Can Kilograms Be Weighed? Evidentally Yes It Can. But, Still Mass Cannot Be Weighed So Kilograms Must Not Exist. Funny Isn't It.
One good thing out of this the next time I'm at the doctors and they want to weigh me I'll tell them mass cannot be weighed.

"Well, I care. I suggest we are on the same side of the discussion though it might not be obvious."

If you will look on SAAMI specs site you will see most standard case head sizes will run around 6.2 to 6.4 percent MAX ALLOWABLE PRESSURE over MAP. Not say that is true for all cartridges (Mr Gibson take note as I am sure I am wrong but I looked at several cartridges) because remember NOTHING is concrete fact.

We Know Mass Cannot Be Weighed But It Has Newtonian Weight And That Is Derived From Kilograms And Kilograms Can Be Converted to Pounds. But, Still Mass Cannot Be Weighed. But How is the kilograms obtained? Can Kilograms Be Weighed? Evidentally Yes It Can. But, Still Mass Cannot Be Weighed So Kilograms Must Not Exist. Funny Isn't It.
One good thing out of this the next time I'm at the doctors and they want to weigh me I'll tell them mass cannot be weighed.

44Mag#1, I'm not looking for argument here and in one sense I agree with your thoughts though I look at it from a perspective that might be different than your own.

On the matter of pressure metrics that I raised previously, It was a rhetorical question to some degree. You refer to percentages which are not unreasonable, I refer to published specs. SAAMI refers to MAP, MPLM (max probable lot mean) and MPSM (max probable sample mean) in establishing their data. They do it with crusher or transducer data sometimes both for each of the cartridges for which they set standards.

The point I was trying to make is the range of variation between the three data references are rather narrow, and as Larry has pointed out, and done so well in my opinion, is that small things matter. A point I would make is that conventional references used by some handloaders such as a shiny belt on a fired cartridge, sticky bolts, loose primer pockets etc. are more than likely far beyond pressure levels required to present such evidence and reliance upon such things is risky to say the least.

A couple of experiences from days gone by if I might, both in the general range of 20 years ago.

#1: I had a Ruger #1 in .22 Hornet that did not shoot particularly well and in the course of conversation with a very qualified 'smith he suggested a K-Hornet conversion. The deal was done, and in the process I picked up my first bottle of Lil Gun powder. The "internet" gurus suggested that 13.0 grains was a good load for the Hornet and I figured that if good for the Goose.... But being a bit cautious I called Hodgdon and spoke with one of their techs, for there was NO data available at that time for the K. He was quite clear that I could not put enough L.G. in a Hornet or K-Hornet case to cause pressure problems and there ya go, right from the horse's mouth.

Now the funny thing is that I could not get 13 grains of LG in a Hornet case. Best I could do with an unfired case was about 12.5 and that became my fireform load. It worked quite well, all things considered. Went to the line, did a FF on 50 cases and then set about reloading them. Off to the range a few days later, set up on the bags at 100 yards and popped off 3 rounds. Shazaam! 1/2" groups right out of the gate. Next series was fired over a Chrony just for giggles. 13.0 gr L.G. filled the case to the shoulder and I had loaded 40 gr Nosler BTs. Group of 5 went into about 3/4" with an average velocity of 3360 fps. At that point I was wondering why anyone would want a .222 or .223 shooter. Extraction was normal, the cases had no tell tale ring at the web, life was good. Right? 3 load cycles later with that brass and the primers fell out of the cases on extraction w/o shiny rings at the web. So much for expert techs and web wisdom. I settled back to 12.5 grains of powder and 3,000 fps avg for that same bullet and called it good. No issues since.

#2: A friend and fellow employee had picked up what was then a new .300 Weatherby and asked if I'd help him get started with it and perhaps load some ammo. Since he wanted to follow up with handloading as well I agreed. Bullet of his choice, brass was once fired Weatherby stock. The load data was abundant and by odd chance I had some which matched components with exception of the rifle. I loaded a box for him and passed them along with very explicit instructions to the point that if he experienced any abnormality in bolt lift or extraction that he was to stop shooting and confer with me prior to further shooting.

The gun and shooter preformed remarkably well insofar as precision went, typically grouping 3 shots in less than an inch @ 100 yards. Over the course of several weeks we increased the load in small increments. My normal path on such things is no more than 1 grain on round 2 and at the mid point between suggested starting loads and max loads I revert to .5 grain increments. At the point where we had spanned half of that gap or about 2.5-3 grains of charge increase he returned the brass after a range session, laughing about the fact they had to beat on the bolt with a piece of 2x4 to open the action. He and his shooting buddy thought it vastly amusing. I opened the box and all cases were empty. Asked him if it was the last round that did this and he smiled, said "No, they all were like that." I handed the brass back to him and wished him luck. The load in question was 3 grains under load manual maximum charge for that specific bullet/primer/powder/COAL combination.

I'm not an engineer, but tend to think like one most days due to frequent affiliation with such people, and the fact that I spent several years examining the pieces of aircraft accidents and figuring out what went wrong. Just like handloading mishaps, most aircraft crash due to pilot error. Those caused by design or mechanical malfunction are rare, albeit interesting, once the blood has dried and the smell dissipates.

My point is pretty much your own. Caution is appropriate and there is little reward for heroics, unless one happens to be an ER surgeon. Facts are where you find them and conventionally accepted clues in this game are far from reliable.

MAP stands for maximum average pressure. What is the max peak pressure for the cartridges?

SAAMI uses a statistical method to determine that based on the Extreme Variation derived from the knowledge of the population standard deviation of any lot of ammunition using the Relative Range Tables (Biometrika Tables for Statisticians) A Maximum EV is calculated from the MPSM for the cartridge. The MPSM for the 30-06 is 63,800 psi, after that your guess is as good as mine........

All that is a little above my pay grade so I prefer to go with the SAAMI MAP for most cartridges. I do, in some cases given a modern action, new brass and actually measuring the psi, load to the 62 - 65,000 psi range with certain cartridges of '06 head size. The SAAMI MAPs are derived by putting the pressure level two standard errors below the MPLM pressure in order to assure a 97.5% probability that the MPLM is not exceeded. To me that seems a good safe fudge factor.

Last edited by Larry Gibson; 10-10-2017 at 10:08 PM.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

Completed the 3rd test with no real change in the result; The max load of H4350 under 180 gr bullets in the 30-06 cartridge as listed in Hodsdon’s #27 Data Manual and Speer’s Reloading Manual #14 give pressures in excess of the SAAMI MAP for the 30-06 cartridge.
I finished testing this morning at the same range. The M43 Oehler was set up as usual and the same test rifle was used. Temperature was a mild 65 degrees with no wind. No problems were encountered during the testing. The barrel was allowed to cool and was cleaned between tests. Tests include the fouler shot which many times increases the ES and SD slightly. However, with this test barrel the results are usually not skewed enough to denigrate the results.

After set up and a systems check of the M43 I shot a five shot “reference ammunition” test using the same very uniform lot of M72 Match ammunition as previously used. The MAP was 54,400 psi with a velocity of 2540 fps; exactly within the +/- range for that lot of ammunition. The time/pressure curves (traces) were very smooth giving no indication of any abnormality. Had I deleted the fouler shot the velocity would have been 2550 fps……exactly what the velocity for this lot (loaded for M1s to equal the ballistics of M118) is supposed to be.

With the system, including test rifle, measuring velocity/pressures normally and validated the test continued.

The test rifle used has a 24” barrel with a 10” twist. The Winchester cases used were trimmed to 2.484”. The cases were primed with Winchester WLR primers.

The data lists the bullet used as a Sierra 180 SPBT loaded to a cartridge OAL of 3.300”. The test loads were loaded with Sierra 180 gr SPBTs with a Cartridge AOL of 3.300”.

The load data for H4350 shows a maximum load of 57.5 gr for 2798 fps at 49,300 C.U.P.

I unfortunately at this stage of testing the lb of H4350 I had was running short. Thus I decided to conduct my usual initial pressure/velocity test. This is to load 3 shots of each load working up to a listed maximum charge in .5 gr increments. This gives a quick look with a certain cartridge/bullet/powder combination at what the potential velocity would be at a maximum MAP. Thus I loaded 4 rounds of 55.3 (to exclude the fouler) and then 3 rounds each of 55.8 gr, 56.3 gr, 56.8 grand 57.2 gr (just .3 gr under the manual’s 57.5 gr maximum charge). It should be noted the first test of this Hodgdon load I used Federal 210 primers and had ignition problems that gave signs of potential SEE. In this test it should be noted the ignition problems seemed to be negated with the more powerful WLR primer. The pressures are also notably higher.

55.3 gr gave us 2741 fps at 58,900 psi. The traces are smooth and the “rise” figures are also uniform.

55.8 gr gave us 2785 fps at 61,700 fps. At this point this load is 2.2 gr under the maximum load listed in the #27 Data Manual and is already over the SAAMI MAP for the 30-06. The velocity (corrected to the Muzzle) is just short of the 2798 fps listed in the manual. Keep in mind given the same rifle/cartridge/load with an increase in velocity by increasing the powder charge there will be an increase in pressure. Here we are 2.2 gr less than the charge listed in the manual and are getting basically the same velocity. Thus based on the assumption Hodgdon is a member of SAAMI and adheres to SAAMI specifications, given the C.U.P. listed in the manual) there does indeed seem to be something not right with the data concerning H4350 in the 30-06 with 180 gr bullets.

Though at the MAP of the 30-06 I decided to continue the test…..within reason anyway.

56.3 gr gave us 2814 fps at 63,400 psi.

56.8 gr gave us 2844 fps at 65,400 psi. Now if we really wanted to push things and load to the maximum MAP of any ’06 sized case head (65,000) then probably 56.5 gr would be the maximum charge with this bullet.

57.3 gr gave us 2874 fps at 68,100 psi with one shot hitting 71,400 psi. Still .2 gr below the manuals maximum charge this is clearly “excessive”. The primers were flattened and slightly cratered.

All of this is useless some would have us believe. Let the gun tell us? The rifle (gun) told me nothing. There was no hard bolt lift. There was nothing amiss with the functioning of the rifle. Let the cases tell us? The cases extracted normally. There was no indication of excessive case head or expansion ring expansion. The primers were not excessively flattened although at 57.3 gr there was a bit more flattening and a small bit of cratering. Absolutely no indication we were pushing 70,000 psi…….

So had I not an Oehler M43 how would I know I was pushing pressures? The chronograph would tell me so. Looking at the max load in the #27 Data Manual we see the velocity for that charge is 2798 fps. Thus when I work up a load and get close to 2798 fps I can bet I am pushing pressures. It is a fool's errand to believe since the book says I can use more powder that I can do so safely with out excessive pressure.

It is with the advent of common chronographs that when velocities are reached below the charges listed in manuals that we get the myth of the "fast barrel". With velocity comes pressure.....no way around that.

Here’s a picture of the primers. Left to right are unfired WLRs then the cases in the order fired.

My next post will give the details of the velocity/pressure workup using the H4350 data from the Speer #14 Reloading Manual with the Speer 180 SP.

Last edited by Larry Gibson; 10-10-2017 at 11:06 PM.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

It is with the advent of common chronographs that when velocities are reached below the charges listed in manuals that we get the myth of the "fast barrel". With velocity comes pressure.....no way around that.

I generally agree with that statement. While less common today (due to higher BC bullets being allowed) Palma rifles tended to have undersize bores to increase pressure to gain velocity.

About 10 years ago I built 3 identical 6mm BR's on Tikka 595 actions. One for myself and one each for friends. I ordered three identical barrel blanks from Krieger. When they came in the bores and groove were within a .0001". Serial numbers were consecutive. No way to tell if they were from the same piece of bar stock. All chambered with the same carbide reamer and headspace were within .001". Basically as identical has possible yet one was consistently 150 per second slower.

Last year I chambered two NON Krieger barrels. Spec's. were a couple of tenths different but nothing I was concerned about. From the borescope I could not tell a surface finish difference. One had normal barrel break in copper fouling. The other has about 1,500 rounds through it. It never stopped heavily copper fouling and the maker basically said go fly a kit. Same owner not mine so I don't have any chrono data. The owner is having me replace the copper fouler this winter with a Krieger.

Okay, with the chrono we know we can detect potentially high pressure. We all agree on that. I own a chrono.
Now what do you recommend for those that don't own a chrono?
For the interest of safety explain how these individuals should look for loads that are out of specs enough that they need to be toned down.
Plying us with pressure data is good but what about the individuals without chronos to at least measure velocity.
Are they out of luck? Do they at least need to spring for a chrono or fly by the seat of their pants and hope for the best or what?

We Know Mass Cannot Be Weighed But It Has Newtonian Weight And That Is Derived From Kilograms And Kilograms Can Be Converted to Pounds. But, Still Mass Cannot Be Weighed. But How is the kilograms obtained? Can Kilograms Be Weighed? Evidentally Yes It Can. But, Still Mass Cannot Be Weighed So Kilograms Must Not Exist. Funny Isn't It.
One good thing out of this the next time I'm at the doctors and they want to weigh me I'll tell them mass cannot be weighed.

Okay, with the chrono we know we can detect potentially high pressure. We all agree on that. I own a chrono.
Now what do you recommend for those that don't own a chrono?
For the interest of safety explain how these individuals should look for loads that are out of specs enough that they need to be toned down.
Plying us with pressure data is good but what about the individuals without chronos to at least measure velocity.
Are they out of luck? Do they at least need to spring for a chrono or fly by the seat of their pants and hope for the best or what?

They fly by the seat of their pants just like we all did prior to the advent of available chronographs.

Please don't get the wrong idea about this thread. I am not criticizing any loading manual. I am certainly not saying or insinuating that all data in loading manuals is suspect. This thread, i.e. the topic here, is simply that an error has been found with H4350 in the 30-06 with 178 - 180 gr bullets. All the pressure data I am posting is simply documenting that suspected error.

The manuals all say to work up loads. They also say if you change a component in a worked up load to re-work up the load. Yet both Hornady and Spear lump several of their similar weight bullets under the same load data. None of the manuals tell reloaders to track the lot numbers of the various components and to rework up the load if a different lot number is used. Mr. reloader most often doesn't. In loading for his '06 he buys a lb of the same powder without any idea of "lot to lot variation"), a box of the same primers (maybe, probably will just buy large rifle primers) and a box of the same 180 gr bullets (again maybe, many times he will just bask for a box of 180 gr bullets). Mr reloader goes on the assumption, as do almost all reloaders, that if he stayed with in the load manual data with his load it was safe. That assumption by most all reloaders is that a lb of H4350 is a lb of H4350 the same as any other lb of 4350. Mr reloader also believes 180 gr bullets are 180 gr bullets and large rifle primers are large rifle primers. A few of us may know better and even some manuals, buried deep in the fine print of their text, they also say there can be a difference. Well and fine but Mr reloader doesn't read the fine print of the text in the manuals, especially these days with load data taken from sites or forums. Odds are Mr reloader never read the fine print in his manual......he just went straight to the data pages and then most often to the maximum load. After all it's in the manual so it's safe, right? Most of the manuals say to watch for the "usual pressure signs" and to stop even if the load is under the maximum. That is good advise seldom followed by Mr reloader.

Point is Hodgdon, Hornady and Speer (the manuals used in this thread) know that. That is why their data is almost always safe to use as they stay with in SAAMI specifications now. However, just as I am not infallible, neither are they. Mistakes do occur no matter how careful they are/we are. I am, in this thread pointing out one mistake.

As I have mentioned before; reloaders who are not that experienced or who do not have a chronograph or access to one will do well to heed the advise of the manuals and stay within the manual data. Even with in that manual data loose primer pockets after 1 - 3 firings is a sure bet the pressure is excessive.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

The Data in Speer’s Reloading Manual #14 for the 30-06 using H4350 with 180 gr bullets lists a starting charge of 54.0 gr and a maximum charge of 58.0 gr. Note the data is for use with five different Speer bullets of 180 gr weight. The velocity for the maximum charge is listed at 2756 fps. The test rifle was a M700 Remington with a 22” barrel. Also IMR4350 is also listed with a maximum load of 56 gr at 2639 fps and AA4350 is listed with a maximum charge of 57 gr at 2615 fps. Both of those loads are somewhat low in respect to past test of both powders with different 180 gr bullets. Given a 22” barrel 2700 fps can usually be expected w/o exceeding the SAAMI MAO of 60,000 psi. However my test rifle has a 24” barrel so a velocity of 2750 to 2780 fps should be just about at the SAMMI MAP with a powder of H4350’s burning rate.

Speer used Winchester cases trimmed to 2.484”, a maximum OAL of 3.340” and CCI 200 primers. The maximum load charges were also denoted as being compressed.

For my test I used the Speer 180 gr SP, Winchester cases trimmed to 2.484”, CCI 200 primers and an AOL of 3.330” (just of the lands of the test rifle). I was initially concerned about the use of the CCI 200 primer as it is about on the same brisance level as the Federal 210 which gave ignition and potential SEE problems in a previous test. The test rifle had a verification test of M72 Match reference ammunition fired prior to this test. The pressures and velocity of that test were within normal variance and were actually quite uniform.

As I was just about out of H4350 and could not find any locally I used my standard initial pressure work up test. This is loading three round of each charge from the start charge to the maximum charge in .5 gr increments. This gives us a velocity to pressure relationship that can quickly, with minimal expenditure of components, tell us what velocity (+/-) we can expect at a chosen maximum pressure level. Then with that narrowed down we can tweak the loads in a narrower range under the maximum pressure with ten shot groups for accuracy.

I started at Speer’s start load of 54.0 gr for the 1st test. It produced 2599 fps (all average velocities are corrected to the muzzle by the M43 Oehler) at 52,800 psi. The pressure traces are normal showing no sign of ignition problems.

54.5 gr gave us 2636 fps at 54,000 psi. Again normal traces and all was looking good.

55.0 gr gave us 2692 fps at 56,900 psi. Notice a little bit of a stutter beginning to appear at the start of the trace which is similar to the beginning of ignition problems I encountered using Federal 210 primers with this powder.

55.5 gr gave us 2719 fps at 58,300 psi. This is the classic 30-06 level load with a 180 gr bullet; 2700 fps just under the SAAMI MAP. Problem though…..the small stutters at the beginning of the traces are becoming more pronounced. Notice the small spikes with a slight let off of pressure.

56.0 gr gave us 2743 fps right at the SAAMI MAP of 60,000 psi. Here, with 2 gr less H4350, we are very close to the velocity listed for the maximum charge at 2756 fps. Were I developing a load with the use of a chronograph I would quit there and consider that a max load in my rifle. The small pressure spikes are still there.

56.5 gr gave us 2761 fps at 61,000 psi. Above the SAAMI MAP but still useable in modern bolt actions were it not for the small pressure anomalies that are still there.

57.0 gr gave us 2783 fps at 62,900 psi. The load is at 100% load density and we can plainly see the beginning of the bullet stopping momentarily and then moving again as evidenced in the trace of the 1st shot. It appears as the powder column in the case is compacted the soft brisance of the CCI 200 primer is not igniting the powders well.

57.5 gr gave us 2803 fps at 64,100 psi. Note the pressure anomalies on the traces, especially the spike on the 2nd shot trace that’s where the bullet sticks in the bore just ahead of the leade. The pressure lets off as the bullet begins moving…….not good.

58.0 gr, the maximum charge gave us 2823 fps at 65,300 psi. Definitely excessive pressure by some 5,300 psi over the SAAMI MAP. Also definite and pronounced ignition anomalies.

As with the data in Hodgdon’s Data Manual #27 the maximum charges of H4350 in the 30-06 used with one of the suggested bullets gives excessive pressure for the 30-06 cartridge. The maximum charge Hornady lists for use with 178 – 180 gr bullets is 55.3 gr. The tested charges very close to that of 55.0 – 55.5 g H4350 with the Sierra 180 gr SPBT and the Speer 180 SP have proven to be in line velocity and pressure wise with Hornady’s data.

Note; as previous testing has shown using a primer such as the Winchester WLR will raise the pressures 3 – 5,000 psi. Using a true magnum primer such as the Federal 215 will raise the pressure even more dramatically. The WLR and the magnum primers have sufficient brisance that ignition is not the problem it is with the Federal 210 and CCI 200 primers.

After 158 test rounds velocity and pressure tested with H4350 under 175 - 180 gr bullets in the 30-06 my suggestion is; if using H4350 in the 30-06 with 178 – 180 gr bullets use WLR primers, start at 53.5 gr and work up to 55.0 gr if wanting to keep the pressure at or below the SAAMI MAP for the 30-06. If, in a modern bolt action rifle, you want to venture into the MAP levels of the 22-250, 25-06, 270W, etc. then consider 55.3 gr as a maximum load, again using WLR primers.

Last edited by Larry Gibson; 10-12-2017 at 03:37 PM.

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla

..........About 10 years ago I built 3 identical 6mm BR's on Tikka 595 actions. One for myself and one each for friends. I ordered three identical barrel blanks from Krieger. When they came in the bores and groove were within a .0001". Serial numbers were consecutive. No way to tell if they were from the same piece of bar stock. All chambered with the same carbide reamer and headspace were within .001". Basically as identical has possible yet one was consistently 150 per second slower. .

Question; did you test them yourself consecutively with identically loaded cartridges?

Larry Gibson

“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla